Device for throwing the cranks of engines off the dead-center



No Mode1. 2 Sheets-Sheet 1.

J. W. FREEMAN. DEVICE FORTHROWING THE GRANKS 0F ENGINES OFF THE DEAD CENTER. Y

No. 450,000. I Patefited Apr. 7, 1891.

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(No Model.) 2 Sheets-Sheet 2,

J. WLPREEMAN. DEVICE FOR THROWING THE GRANKS 0P ENGINES OFF THBDEAD CENTER. No. 450,009. Patented Apr. 7, 1891,.

UNITE-D STATES PATENT JOHN w. FREEMAN, or JOPIJIN, MISSOURI.

DEVICE FOR THROWING THE CRANKS F ENGINES OFF THE DEAD-CENTER.

SPECIFICATION forming part of Letters Patent No. 450,009, dated April '7, 1891.

Application filed September 30, 1890. Serial No. 366x644- (No model.)

To all whom it may concern;

Be it known that I, JOHN W, FREEMAN, a citizen of the United States, andaresident of Joplin, in the county of Jasper and State of Missouri, have invented certain new and useful Improvements in Devices for Throwing the Cranks of Engines off the Dead -Center; and I do hereby declare that the following is a full, clear, and exact description of the inventiongwhich will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, which form a part of this specification.

My invention relates to improvements in devices for throwing the cranks of steam and other engines off the dead-center.

In single-cylinder engines much difficulty is sometimes experienced in starting the same, owing to the cranks being on a dead-center that is to say, in line with the connectingrods. A number of contrivances have been devised for throwing the cranks and connecting-rods out of line, so that the engines can be started; but they have proved more or less objectionable and have not been introduced into general public use.

The object of my invention is to provide means to be used in connection with steam and other engines, and the driving-shaft, and balance-wheels thereof, whereby the cranks may be thrown off the dead-center in a reliable and eflicient manner.

The invention consists in the novel construction and combination of parts hereinafter fully described, and specifically pointed out in the claim.

In the accompanying drawings, Figure 1 is a side elevation of the balance-wheel of a steam-engine with my improvements applied thereto. Fig. 2. is an end view of the same, the balance-wheel being partly broken away. Fig. 3 is a detail perspective view of the cage carrying the movable roller.

In the said drawings, the reference-numeral 1 designates the frame in which the drivingshaft 2 is journaled. This shaft carries at one end a balance-wheel 3,.securely fixed thereto, and is also provided with the usual crank. (Not shown.) I

The numeral 6 designates a hub, loosely encircling the end of shaft 2, so as to be capable of oscillating thereon. This hub has secured to or formed with it two oppositely-extending horizontal arms 7 and S and a downwardlyextending vertical arm 9. The arm '7 at its outer or free end is provided with a cage 10, having a downwardly-extending projection 12. This cage is provided with an L-shaped recess 13, in which is inserted a movable roller 14, the lower portion of said recess being made tapering, as shown. The arm 8 has at its free end a weight 15, which serves as a counterbalance for the arm 7. Pivoted to the end of arm 9 is .a horizontal bar 16, which is connected to the lower end of a lever 17, pivoted at 1-8, to any suitable support.

The operation is as follows: In its normal position the parts occupy the position shown in Fig. 1, with the roller 14 resting loosely in the upper or horizontal portion of the L- shaped recess. If the shaft should have stopped on the dead-center and it is desired to start the engine, the lever 17 is thrown over to the point 19, as shown by dotted lines Fig. 1. This will cause the arm 8 to be depressed, when the roller 11 will drop out ,of the horizontal portion of the recess into the tapering or vertical p0 tion thereof, and come into frictional contact with the inner face of the rim of the balance-wheel. By now throwing the lever back to the point 20 the arm 8 will be elevated, and by reason of the frictional contact between the rim of the wheel and the roller, and consequently its shaft, will be rotated a short distance and the crank thrown off the center. The piston will then begin to work, rotating the shaft and wheel and causing the roller to be moved back into recess 10, when the counterbalanced arm 8 will return the parts to normal position.

Having thus described my invention, what I claim is:

The combination, with a driving-shaft and a balance-wheel mounted thereon, of a hub loosely mounted on said shaft having an arm In testimony that I claim the foregoing as provided at its free end with an L-shaped remy own Ihave hereuntoaffixed my signature [0 cess, a movable roller Working in said recess in presence of two witnesses.

and adapted to engage with the rim of the 7 T- 1 T 5 balance wheel, a counterbalanced arm, a JOHN FREEMAN vertical arm, a connecting-bar, and a pivoted Witnesses: lever connected with said bar, substantially SAML. E. MCCRAOKEN,

as described. CHARLES H. MONTGOMERY. 

